from typing import Callable


def _convert_and_print(func: Callable[[str], str], original: str):
    print(func(original))


def _main():
    s = "Python Programming Language"
    _convert_and_print(str.lower, s)
    _convert_and_print(str.upper, s)

    count_ns: Callable[[str], str] = lambda a_string: a_string.count("n")
    _convert_and_print(count_ns, s)

    split_white: Callable[[str], str] = lambda a_string: a_string.split()
    _convert_and_print(split_white, s)

    replace_white_to_commas: Callable[[str], str] = lambda a_string: a_string.replace(" ", ",")
    _convert_and_print(replace_white_to_commas, s)


if __name__ == "__main__":
    _main()
